o Adding elfinfo tool from the stm32 playground.

3 files changed, 274 insertions, 0 deletions

diff --git a/cmake/elfinfo/.gitignore b/cmake/elfinfo/.gitignore
new file mode 100644
index 0000000..485dee6
--- /dev/null
+++ b/cmake/elfinfo/.gitignore
@@ -0,0 +1 @@
+.idea
diff --git a/cmake/elfinfo/CMakeLists.txt b/cmake/elfinfo/CMakeLists.txt
new file mode 100644
index 0000000..82efcdf
--- /dev/null
+++ b/cmake/elfinfo/CMakeLists.txt
@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.2)
+
+project(elfinfo CXX ASM)
+
+add_executable(elfinfo elfinfo.cpp)
+target_compile_options(elfinfo PUBLIC "--std=c++14")
+target_link_libraries(elfinfo elf)
+
+INSTALL(TARGETS elfinfo
+        RUNTIME DESTINATION bin
+        LIBRARY DESTINATION lib
+        ARCHIVE DESTINATION lib
+)
diff --git a/cmake/elfinfo/elfinfo.cpp b/cmake/elfinfo/elfinfo.cpp
new file mode 100644
index 0000000..05a847a
--- /dev/null
+++ b/cmake/elfinfo/elfinfo.cpp
@@ -0,0 +1,260 @@
+#include <cctype>
+#include <cstdlib>
+#include <gelf.h>
+#include <err.h>
+#include <sysexits.h>
+#include <fcntl.h>
+#include <cstdio>
+#include <cstring>
+#include <vector>
+#include <algorithm>
+#include <getopt.h>
+#include <inttypes.h>
+#include <elf.h>
+
+using std::vector;
+
+enum class SectionType {
+    TEXT, DATA
+};
+
+const char *to_str(const SectionType &type) {
+    switch (type) {
+        case SectionType::TEXT:
+            return "text";
+        case SectionType::DATA:
+            return "data";
+    }
+}
+
+struct Section {
+    SectionType type;
+    const Elf64_Addr start;
+    const Elf64_Addr end;
+    const Elf64_Xword size;
+    Elf64_Addr used;
+
+    Section(SectionType type, Elf64_Addr start, Elf64_Xword size) : type(type), start(start), size(size),
+                                                                    end(start + size), used(0) {
+    }
+
+    bool contains(Elf64_Addr address, Elf64_Xword size) const {
+        return contains(address) && contains(address + size);
+    }
+
+    bool contains(Elf64_Addr address) const {
+        return start <= address && address < end;
+    }
+};
+
+vector<Section> sections;
+
+char *filename = NULL;
+
+char *program;
+
+__attribute__((noreturn))
+void usage(const char *reason = NULL) {
+    if (reason != NULL) {
+        fprintf(stderr, "%s\n", reason);
+    }
+    fprintf(stderr, "usage: %s -f file [-t start:size] [-d start:size]\n", program);
+    fprintf(stderr, "  -t/-d/-b: add text/data section\n");
+    fprintf(stderr, "At least one section has to be specified\n");
+    exit(EX_USAGE);
+}
+
+void parse_start_size(char *input, Elf64_Addr &start, Elf64_Xword &size) {
+    char *str_size = strchr(input, ':');
+
+    if (str_size == NULL) {
+        usage("bad section specification, missing ':'");
+    }
+
+    *str_size = '\0';
+    str_size++;
+
+    if (sscanf(input, "%" SCNi64, &start) != 1) {
+        usage("bad section specification, could not parse start number");
+    }
+
+    size_t str_size_len = strlen(str_size);
+
+    if (str_size_len < 1) {
+        usage("bad section specification");
+    }
+
+    char suffix = str_size[str_size_len - 1];
+    int modifier;
+
+    if (!isdigit(suffix)) {
+        switch (suffix) {
+            case 'k':
+            case 'K':
+                modifier = 1024;
+                break;
+            case 'm':
+            case 'M':
+                modifier = 1024 * 1024;
+                break;
+            default:
+                usage("bad size modifier, only 'k' and 'M' are allowed");
+        }
+    } else {
+        modifier = 1;
+    }
+
+    if (sscanf(str_size, "%" SCNi64, &size) != 1) {
+        usage("bad section specification, could not parse size number");
+    }
+    size = size * modifier;
+}
+
+bool debug = false;
+
+void parse_args(int argc, char **argv) {
+    int c;
+
+    while ((c = getopt(argc, argv, "Df:t:d:")) != -1) {
+        switch (c) {
+            case 'D':
+                debug = true;
+                break;
+            case 't':
+            case 'd': {
+                Elf64_Addr start;
+                Elf64_Xword size;
+                parse_start_size(optarg, start, size);
+                SectionType type = c == 't' ? SectionType::TEXT : SectionType::DATA;
+                sections.push_back(Section(type, start, size));
+                break;
+            }
+            case 'f':
+                filename = optarg;
+                break;
+            case '?':
+                if (optopt == 'c')
+                    errx(EX_USAGE, "Option -%c requires an argument.\n", optopt);
+                else
+                    errx(EX_USAGE, "Unknown option `-%c'.\n", optopt);
+            default:
+                abort();
+        }
+    }
+
+    if (filename == NULL || sections.empty()) {
+        usage();
+    }
+}
+
+void to_iso(Elf64_Addr i, char *buf) {
+    const char *suffix;
+    if (i > 1024 * 1024) {
+        i /= 1024 * 1024;
+        suffix = "M";
+    } else if (i > 1024) {
+        i /= 1024;
+        suffix = "k";
+    } else {
+        suffix = "";
+    }
+    sprintf(buf, "%" PRIu64 "%s", i, suffix);
+}
+
+int main(int argc, char **argv) {
+    program = argv[0];
+    parse_args(argc, argv);
+
+    if (elf_version(EV_CURRENT) == EV_NONE)
+        errx(EX_SOFTWARE, "ELF library initialization failed: %s", elf_errmsg(-1));
+
+    int fd;
+    if ((fd = open(filename, O_RDONLY, 0)) < 0)
+        err(EX_NOINPUT, "open \"%s\" failed", argv[1]);
+
+    Elf *e;
+    if ((e = elf_begin(fd, ELF_C_READ, NULL)) == NULL)
+        errx(EX_SOFTWARE, "elf_begin() failed: %s.", elf_errmsg(-1));
+    if (elf_kind(e) != ELF_K_ELF)
+        errx(EX_DATAERR, "%s is not an ELF object.", argv[1]);
+
+    size_t shstrndx;
+    if (elf_getshdrstrndx(e, &shstrndx) != 0)
+        errx(EX_SOFTWARE, "elf_getshdrstrndx() failed: %s.", elf_errmsg(-1));
+
+    size_t program_header_count;
+    if (elf_getphdrnum(e, &program_header_count) != 0)
+        errx(EX_DATAERR, "elf_getphdrnum() failed: %s.", elf_errmsg(-1));
+
+    size_t text_size = 0, data_size = 0, bss_size = 0;
+    for (int i = 0; i < program_header_count; i++) {
+        GElf_Phdr phdr;
+
+        if (gelf_getphdr(e, i, &phdr) != &phdr)
+            errx(EX_SOFTWARE, "getphdr() failed: %s.", elf_errmsg(-1));
+
+        if (phdr.p_type == PT_LOAD) {
+            SectionType expectedType;
+            size_t *size;
+
+            if (phdr.p_flags == (PF_X | PF_W | PF_R) || phdr.p_flags == (PF_X | PF_R)) {
+                if (debug) {
+                    printf("Adding PH #%d as text\n", i);
+                }
+
+                expectedType = SectionType::TEXT;
+                size = &text_size;
+            } else if (phdr.p_flags == (PF_R | PF_W)) {
+                expectedType = SectionType::DATA;
+                if (phdr.p_filesz > 0) {
+                    if (debug) {
+                        printf("Adding PH #%d as data\n", i);
+                    }
+                    size = &data_size;
+                }
+                else {
+                    if (debug) {
+                        printf("Adding PH #%d as bss\n", i);
+                    }
+                    size = &bss_size;
+                }
+            } else {
+                warnx("Unknown flag combination: 0x%02x", phdr.p_flags);
+                warnx("Unknown flag combination: 0x%02x", PF_X | PF_R);
+                continue;
+            }
+
+            auto s = std::find_if(sections.begin(), sections.end(), [&](Section &section) {
+                return section.type == expectedType && section.contains(phdr.p_vaddr, phdr.p_memsz);
+            });
+
+            if (s == sections.end()) {
+                fprintf(stderr,
+                        "Could not find a section for elf header #%d of type %s, at address 0x%08" PRIx64 " with size %" PRId64 "\n",
+                        i, to_str(expectedType), phdr.p_vaddr, phdr.p_memsz);
+            }
+            else {
+                (*s).used += phdr.p_memsz;
+
+                *size += phdr.p_memsz;
+            }
+        } else {
+            // ignored
+        };
+    }
+
+    printf("Size by sections\n");
+    printf("Type    Start      End  Size   Used\n");
+    std::for_each(sections.begin(), sections.end(), [&](Section &s) {
+        char size[100];
+        to_iso(s.size, size);
+        int used_pct = (int) (double(s.used) / double(s.size) * 100.0);
+        printf("%4s %08" PRIx64 " %08" PRIx64 " %5s %6" PRId64 " %3d%%\n", to_str(s.type), s.start, s.end, size, s.used,
+               used_pct);
+    });
+
+    printf("\n");
+    printf("Size by type\n");
+    printf("text=%zu, data=%zu, bss=%zu\n", text_size, data_size, bss_size);
+    return EXIT_SUCCESS;
+}